Unit Data

(Select from the criteria below to view unit data charts of NNAP results from 2014 to 2017, for any neonatal unit or network.)

Please note that from 2017 data onwards, we report outlier analysis and main report measures using
a “no imputation” approach. By this we mean that rates of adherence to standards, or rates of
clinical outcomes are described for the babies where the outcome is known. This means that the
2017 results may not be directly comparable with results from 2016, 2015 and 2104 as displayed in
the annual report, unit and network data sections and poster downloads. In previous years missing
data were counted as negative outcomes or non-adherence to standards.

All outlier data and longitudinal outlier data are reported using the “no imputation” approach for all years, so are comparable.

You can use the longitudinal outlier analysis section to consider change in unit and network
performance for the following measures; Antenatal steroids; Temperature on admission;
Consultation with parents; ROP screening; Antenatal magnesium sulphate; Breastmilk feeding at
discharge; Two-year follow-up.

Unit data help

In a caterpillar plot, units are presented from left to right in the ascending order of their
performance on the measure, with the most adherent shown on the right side of the graph. The
performance on the measure (compliance) is shown by the vertical axis. Each unit is represented by
a dot, with a vertical bar above and below the dot representing uncertainty (statistically the 95%
confidence interval) in this measurement of performance.

Although units are ranked for presentation, the purpose of the plot is to demonstrate the variation
rather than to describe differences between units with statistical confidence. Readers should
therefore use these plots to assert differences between units with caution because the observed
differences may have arisen by chance.

Explaining treatment effect

“Treatment effect” is the difference between the rate of BPD or death in babies cared for in a neonatal network compared to the observed rate for a matched group of babies with very similar case mix, cared for in all neonatal units. A positive treatment effect indicates that the rate of BPD or death is higher in the network of interest than for a comparable group of babies cared for in all neonatal units. Where the 95% confidence interval for this effect excludes 0, the treatment effect is unlikely to be a chance finding.

As an example, consider the combined rate of BPD or death in the Northern region. It is the highest of the networks’ rates, and the 95% confidence intervals indicate that this is not a chance finding. However, within the network treatment effect analysis, babies cared for in the Northern region had comparable rates of BPD or death compared to those cared for in all participating units – and therefore only a small treatment effect, whose 95% confidence intervals cross zero. Therefore it is likely that explanations other than how babies are cared for in the Northern region explain the high reported rates of BPD or death.

By contrast the upper panel shows that the combined rate of BPD or death in the South East Coast Neonatal Network is lower than the national rate. When the rate of BPD or death for a set of babies matched to those cared for in the South East Coast Neonatal Network is compared, a negative treatment effect is observed, with 95% confidence intervals excluding zero. This suggests that treatment in South East Coast Neonatal Network is associated with 3.9% lower rates of BPD or death.